AUTOMATIC SLIDING DOOR ISSUES

The driver's side automatic sliding door, when opened, will not stay shut. When I lock it, either by using the master locking system or the manual door lock, it will stay shut, but then dings incessantly. After an hour of trying different a combination of solutions, I am able to get the door closed, and the dinging stopped. However, each time I open that door (to vacuum/clean the car), the whole process starts again. There is no debris in the track, the contact plates are clean, and I've cleaned and lubricated all areas as suggested in previous posts. But still the problem remains. I'm completely frustrated ! There must be a way to solve this problem once and for all. Any solutions?